Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a3135fcae1c395f…

MALICIOUS

PDF

79.3 KB Created: 2021-04-17 11:14:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-07
MD5: 15108e85706e9547413e6ca1a14181ab SHA-1: 74bd9e4ef99ab81487cfe8fcf30b05c9634d3784 SHA-256: 7a3135fcae1c395ff2eb83aade42c0715972c29c10256877ab86c8ded611910c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to disposable domains and are likely part of a link farm designed to redirect users. The document body, though heavily obfuscated, suggests a lure related to research papers, aligning with phishing or malware distribution tactics. No scripts were extracted, but the presence of external URIs indicates an attempt to lead the user to a malicious resource.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ponafet.ru/strik?utm_term=ejemplos+de+investigaci%25C3%25B3n+explicativa+pdf PDF link annotation
    • http://freshka.fun/163695744035amo1.pdfIn PDF document text
    • http://bosemefawixuwov.mypressonline.com/mozopadax.pdfIn PDF document text
    • http://particuliers-societegenerale.xyz/grivel_ghost_ice_axe_reviewowmjc.pdfIn PDF document text
    • https://dubitofux.weebly.com/uploads/1/3/4/4/134458445/cc233.pdfIn PDF document text
    • http://aires.fun/international_business_management_degree_in_sri_lankavt9dx.pdfIn PDF document text
    • https://lebabipiw.weebly.com/uploads/1/3/0/9/130968925/zesazova.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4375885/normal_5ffb6afad387b.pdfIn PDF document text
    • http://finoginujowiwi.mypressonline.com/lanawegawele.pdfIn PDF document text
    • http://graatorama.fun/toastmasters_table_topic_ideas56f2g.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369495/normal_5fe79e59713c3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466161/normal_604510e54bd37.pdfIn PDF document text
    • http://wugegifa.getenjoyment.net/recetas_de_comidas_saludables_peruanas.pdfIn PDF document text
    • http://republvinb.fun/airtel_dth_remote_appx5bbo.pdfIn PDF document text
    • http://nafigunagofadab.getenjoyment.net/barron_toeic_test_4th_edition_free_download.pdfIn PDF document text
    • https://kaxukododeregoz.weebly.com/uploads/1/3/0/9/130969338/rexolusenul-kejixadex-wedumopuw-buzuz.pdfIn PDF document text
    • https://nomozusosowewox.weebly.com/uploads/1/3/1/4/131453154/xuvafivik.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/pavujiniz/mijodowamikalanuwazape.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bc293faf-47e3-4bd1-bf31-7d974d997c92/66697190195.pdfIn PDF document text
    • https://s3.amazonaws.com/nijosinizo/huffy_highland_mountain_bike_reviews.pdfIn PDF document text
    • https://s3.amazonaws.com/jokotaziweluge/rivaxebumojakusexubu.pdfIn PDF document text
    • http://kopurelotalad.onlinewebshop.net/lienzo_modelo_de_negocio_canvas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eaf24994-8d71-4589-ad8f-a5525fe14689/how_to_adjust_time_casio_watch_analog.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2dd06943-e3a8-4481-83cb-505ed83dade5/7168440929.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/43b777e2-7f6c-4377-970a-d0d7abac7360/german_longsword_stances.pdfIn PDF document text
    • https://s3.amazonaws.com/wezukep/4022906312.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f328.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF328 5676 bytes
SHA-256: 051866fd04f59e10bfcaf0abc69fac6e0fc1ac56dcc4d73d909b6a3e4d105f99
font_01_sfnt_off00010648.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10648 11992 bytes
SHA-256: 832d84aeea804b2fe9f9ce8a62d043473462a202bdc1f14d2285567d6e7c659f